1. If the DSM and ICD lead to a different diagnosis can this be an issue of reliability? I have always assumed not. I interpret this as a validity issue (concurrent validity). Some textbooks are getting me confused though. I feel that reliability of diagnosis refers to whether the same set of symptoms would get the same diagnosis from different psychiatrists. (inter rater-reliability) A diagnosis is also reliable if the diagnosis is consistent over two different time periods for the same patient using the same psychiatrist. (test-retest reliability). So reliability is about consistency of diagnosis between psychiatrists not more than one classification system?
2. Rosenhan - I have seen inconsistences in published sources, websites and mark schemes as to whether Rosenhan's study shows problems with the reliability of diagnosis. My understanding and interpretation is the study shows good reliability using DSM (II?) as 7/8 of the diagnoses were the same (Schizophrenia in remission) however shows low validity as the diagnosis was incorrect (although Spitzer does counter argue this).
Would really like your views on this.